diff options
author | Bean Huo 霍斌斌 (beanhuo) <beanhuo@micron.com> | 2014-12-17 07:35:45 +0000 |
---|---|---|
committer | Brian Norris <computersforpeace@gmail.com> | 2015-01-07 11:33:22 -0800 |
commit | 548cd3ab54da10f896daa7ca422236847a915734 (patch) | |
tree | b639d9d85db919c3ddfbf4be097cd25ab08f7e87 /drivers | |
parent | ed0215cc3b5292fc0f4af70e29dc61fa2d0aa76c (diff) |
mtd: spi-nor: Add quad I/O support for Micron SPI NOR
This patch adds code which enables Quad I/O mode on Micron SPI NOR flashes.
For Micron SPI NOR flash, enabling or disabling quad I/O protocol can be
done By two methods, which are to use EVCR (Enhanced Volatile
Configuration Register) and the ENTER QUAD I/O MODE command. There is no
difference between these two methods. Unfortunately, for some Micron SPI
NOR flashes, there no ENTER Quad I/O command (35h), such as n25q064. But
for all current Micron SPI NOR, if it support quad I/O mode, using EVCR
definitely be supported. It is a recommended method to enable Quad I/O
mode by EVCR, Quad I/O protocol bit 7. When EVCR bit 7 is reset to 0,
the SPI NOR flash will operate in quad I/O mode.
This patch has been tested on N25Q512A and MT25TL256BAA1ESF. Micron SPI
NOR of spi_nor_ids[] table all support this method.
Signed-off-by: Bean Huo <beanhuo@micron.com>
Acked-by: Marek Vasut <marex@denx.de>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/mtd/spi-nor/spi-nor.c | 62 |
1 files changed, 54 insertions, 8 deletions
diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c index 0f8ec3c2d015..ea196c18dec9 100644 --- a/drivers/mtd/spi-nor/spi-nor.c +++ b/drivers/mtd/spi-nor/spi-nor.c @@ -560,14 +560,14 @@ static const struct spi_device_id spi_nor_ids[] = { { "mx66l1g55g", INFO(0xc2261b, 0, 64 * 1024, 2048, SPI_NOR_QUAD_READ) }, /* Micron */ - { "n25q032", INFO(0x20ba16, 0, 64 * 1024, 64, 0) }, - { "n25q064", INFO(0x20ba17, 0, 64 * 1024, 128, 0) }, - { "n25q128a11", INFO(0x20bb18, 0, 64 * 1024, 256, 0) }, - { "n25q128a13", INFO(0x20ba18, 0, 64 * 1024, 256, 0) }, - { "n25q256a", INFO(0x20ba19, 0, 64 * 1024, 512, SECT_4K) }, - { "n25q512a", INFO(0x20bb20, 0, 64 * 1024, 1024, SECT_4K) }, - { "n25q512ax3", INFO(0x20ba20, 0, 64 * 1024, 1024, USE_FSR) }, - { "n25q00", INFO(0x20ba21, 0, 64 * 1024, 2048, USE_FSR) }, + { "n25q032", INFO(0x20ba16, 0, 64 * 1024, 64, SPI_NOR_QUAD_READ) }, + { "n25q064", INFO(0x20ba17, 0, 64 * 1024, 128, SPI_NOR_QUAD_READ) }, + { "n25q128a11", INFO(0x20bb18, 0, 64 * 1024, 256, SPI_NOR_QUAD_READ) }, + { "n25q128a13", INFO(0x20ba18, 0, 64 * 1024, 256, SPI_NOR_QUAD_READ) }, + { "n25q256a", INFO(0x20ba19, 0, 64 * 1024, 512, SECT_4K | SPI_NOR_QUAD_READ) }, + { "n25q512a", INFO(0x20bb20, 0, 64 * 1024, 1024, SECT_4K | USE_FSR | SPI_NOR_QUAD_READ) }, + { "n25q512ax3", INFO(0x20ba20, 0, 64 * 1024, 1024, SECT_4K | USE_FSR | SPI_NOR_QUAD_READ) }, + { "n25q00", INFO(0x20ba21, 0, 64 * 1024, 2048, SECT_4K | USE_FSR | SPI_NOR_QUAD_READ) }, /* PMC */ { "pm25lv512", INFO(0, 0, 32 * 1024, 2, SECT_4K_PMC) }, @@ -891,6 +891,45 @@ static int spansion_quad_enable(struct spi_nor *nor) return 0; } +static int micron_quad_enable(struct spi_nor *nor) +{ + int ret; + u8 val; + + ret = nor->read_reg(nor, SPINOR_OP_RD_EVCR, &val, 1); + if (ret < 0) { + dev_err(nor->dev, "error %d reading EVCR\n", ret); + return ret; + } + + write_enable(nor); + + /* set EVCR, enable quad I/O */ + nor->cmd_buf[0] = val & ~EVCR_QUAD_EN_MICRON; + ret = nor->write_reg(nor, SPINOR_OP_WD_EVCR, nor->cmd_buf, 1, 0); + if (ret < 0) { + dev_err(nor->dev, "error while writing EVCR register\n"); + return ret; + } + + ret = spi_nor_wait_till_ready(nor); + if (ret) + return ret; + + /* read EVCR and check it */ + ret = nor->read_reg(nor, SPINOR_OP_RD_EVCR, &val, 1); + if (ret < 0) { + dev_err(nor->dev, "error %d reading EVCR\n", ret); + return ret; + } + if (val & EVCR_QUAD_EN_MICRON) { + dev_err(nor->dev, "Micron EVCR Quad bit not clear\n"); + return -EINVAL; + } + + return 0; +} + static int set_quad_mode(struct spi_nor *nor, struct flash_info *info) { int status; @@ -903,6 +942,13 @@ static int set_quad_mode(struct spi_nor *nor, struct flash_info *info) return -EINVAL; } return status; + case CFI_MFR_ST: + status = micron_quad_enable(nor); + if (status) { + dev_err(nor->dev, "Micron quad-read not enabled\n"); + return -EINVAL; + } + return status; default: status = spansion_quad_enable(nor); if (status) { |